Non-contact rotary torque sensors can deliver power to the electronics carried by a rotatable shaft or the like through the use of inductive technology.
Currently the conventional wisdom for inductive power transfer is a wire-wound concentric transformer consisting of toroidal copper wire-wound coils on a ferrite core.
There are a number of disadvantages to such inductive power transfer systems. In particular, the cores and windings are usually not available “off the shelf” but must be custom designed and built. The cost of custom building ferrite cores is very high. The manufacture of copper wire windings adds additional costs and delivery time delays.